Fast and Compute-efficient Sampling-based Local Exploration Planning via Distribution Learning
Accepted by Robotics Automation Letters (RA-L) & IROS 2022
Lukas Schmid*
Chao Ni*
Yuliang Zhong
Roland Siegwart
Olov Andersson
*equal contribution
All authors are with Autonomous System Lab, ETH Zurich.
[Paper]
[Video]
[GitHub]

Abstract

Exploration is a fundamental problem in robotics. While sampling-based planners have shown high performance and robustness, they are oftentimes compute intensive and can exhibit high variance. To this end, we propose to learn both components of sampling-based exploration. We present a method to directly learn an underlying informed distribution of views based on the spatial context in the robot's map, and further explore a variety of methods to also learn the information gain of each sample. We show in thorough experimental evaluation that our proposed system improves exploration performance by up to 28\% over classical methods, and find that learning the gains in addition to the sampling distribution can provide favorable performance vs. compute trade-offs for compute-constrained systems. We demonstrate in simulation and on a low-cost mobile robot that our system generalizes well to varying environments.


Video


Network Architecture

The encoder and decoder are trained offline in CVAE fashion to learn an underlying distribution view point for a map, given demonstrations of informative samples. The map encoder and gain predictor can be trained independently in supervised fashion. At run-time, any random seed can be drawn from the prior distribution and mapped to an output sample. After a gain is assigned and utility computed, the next action is chosen.

Benchmark Results

Exploration performance in the Maze environment for numbers of samples N={1,5,10,20,50}. We observe that the learnt sampling distribution significantly improves performance, most notably for few samples. As N and therewith coverage increases, the information gain computation becomes more important. For details, please refer to our paper.


Paper and Citation

Lukas Schmid, Chao Ni, Yuliang Zhong, Roland Siegwart, and Olov Andersson
Fast and Compute-efficient Sampling-based Local Exploration Planning via Distribution Learning.
In IEEE Robotics and Automation Letters, June 2022
(hosted on ArXiv)

[Bibtex]


Acknowledgements

This work received funding from the Microsoft Swiss Joint Research Center and a Wallenberg Foundation and WASP Postdoctoral Scholarship. This webpage template was borrowed from here.